One piece wall system



FIG. 1 is a front view of a one piece wall system showing my design;

FIG. 2 is a top view of the one piece wall system;

FIG. 3 is a side view of the one piece wall system; and,

FIG. 4 is a perspective view of the one piece wall system.

The back of the one piece wall system is flat and unadorned and does not form a part of the claimed design. 

I claim the ornamental design for a one piece wall system, as shown and described. 